Conversion of oxymethylenepentenoates to malonaldehydates



Patented Jan. 30, 1951 UNITED STATES PATENT OFFICE CONVERSION OFOXYMETHYLENEPEN- TENOATES TO MALONALDEHYDATES John 0. Van Hook,Philadelphia, and Willard J. Croxall, Bryn Athyn, Pa., assignors toRohm"& Haas Company, Philadelphia, Pa., a corporation of Delaware NoDrawing. Original application January 21,

1949, Serial No. 72,074. Divided and this application January 21, 1949,Serial No. 72,073

5 Claims. (01. 260-483) hydates when they are heated. It is this lastreaction which is here claimed together with the new malonaldehydateswhich result thereby.

In our application Serial No. 72,076, filed on even date, it is shownthat esters of the formula R CH=C (R CH2OCH=CHCOOR+ wherein R is aphenyl group, an alkyl group of not over four carbon atoms, hydrogen,chlorine, or bromine, R. is likewise hydrogen, chlorine, bromine, analkyl group of not over four carbon atoms, or a phenyl group, and R+ isa non-tertiary hydrocarbon group, particularly an alkyl group of notover eight carbon atoms joined to oxygen at a non-tertiary carbon atom,are rearranged by heating at 150 to 250 C. to yield compounds of theformula HOCH=CCOOR+ H R1 he cm It is also shown in the above-identifiedapplication and in Application Serial No. 72,075, filed on even datethat the free hydroxyl group of the rearranged compounds reacts withacid anhydrides to yield acyloxy derivatives.

We have now discovered that these derivatives react with alcohols in thepresence of an acidic catalyst to yield ether esters of the formula Thesituation-inwhich R," is a 2,3un-

ranged is shown in our application Serial No.

The above products are new etheresters which are of considerableinterest. They have unsaturated linkages which give them chemicalreactivity. They are of value in the formation of polymeric products.They react with ureas and thioureas to form uracils and thiouracils.When R has an allylic structure, the new ether esters are rearranged byheating to yield malonaldehydates. Thus, when R has the structure R CH=C(R CH2- the rearranged compound is H0R -C(R )=CHq OCH- oooR+ (or R0)HCR1O(R1)=CH;4

When this compound is heated with an alkali metal hydroxide or alkoxide,such as potassium hydroxide or sodium alloxide, it loses the CO groupfrom the aldehyde group to form esters of the structure R representing2,3-unsaturated hydrocarbon groups.

The starting materials for use in this invention may be derived fromacetylene and a normal ester of carbonic acid. As is shown inapplication Serial No. 52,607, filed by Croxall and tained allylbeta-alloxyacrylate and allyl beta,-

beta-di(alloxy)propionate. Other carbonates may be-used in place ofallyl carbonate, both saturated and unsaturated. In place of the allylgroup-proper, there may be used other 2,3-unsaturated alcohol residues.

It is not necessary, however, to prepare at this stage an ether esterhaving allylic groups. The starting carbonate ester may be that of alower saturated aliphatic alcohol, ROH, such as dimethyl carbonate,diethyl carbonate, dipropyl carbonate, or dibutyl carbonate. These reactwith acetylene between 10 C. and 110 C. in the presenceof an alkalinecatalyst to give corre spqnqing; beta-alkoxyacrylate and beta,beta-dialkoxyp'ropionates. When such an other ester is heated with a2,3-unsaturated alcohol, R'OH, in the presence of an alkaline catalyst,the lower alkyl groups are displaced by the unsaturated alcohol residue,as falls within the purview of application Serial No. 52,601, filed byCroxall and Van Hook on October -2, 1948.

Both the ether and the ester groupings need not, however, be thusreplaced. The alkyl group forming the ether function may be selectivelyreplaced with another alcohol residue. This is accomplished by heatingan alkyl beta-alkoxyacrylate or alkyl beta,beta-dialkoxypropionate withan alcohol ROH, which boils higher than ROH and which is hereunsaturated in the 2,3- position, in the presence of a mildly acidiccatalyst, such as an alkali metal suLate. There is taken from thereaction mixture thealcohol corresponding to the alkyl group, R, and,when an amount of such alcohol as is equivalent to the ether group hasbeen removed, the reaction is interrupted. In this way ether esters ofthe formulae ROCH=CHCOOR and (RO) zCI-ICHzCOOR are obtained as is morefully described in Application Serial No. 52,602, filed by Croxall andVan Hook on October 2, 1948.

The beta,beta-diether propion'ates are converted to beta-monoetheracrylates when the former are heated in the presence of an alcoholysiscatalyst, such as an alkali metal acid sulfate or an alkali, and a moleof alcohol taken off per mole of ester. This process is describe'dindetail in application Serial -No. 52,608, filed by Croxall and Schneideron October 2, 1948. By this process an ether ester such as ethyl beta,beta-diethoxypropionate is converted to ethyl beta-ethoxyacrylate -orallyl beta ,beta-dialloxypropionate is converted to allylbeta-alloxyacrylate.

-In place of the allyl group used above, there may be utilized otherallylicly unsaturated group, particularly a hydrocarbon group or ahalohydrocarbon group. The preferred unsaturated groups are allyl,2-methal1yl, Z-ethallyl, 2- propallyl, 2-butallyl, 2-phenallyl,2-chlorallyl, 2-bromallyl, 3-chlorallyl, 3-bromallyl, 3-methallyl(crotyl), 3-ethallyl, 3-propallyl, '3-'butallyl,

and S-phenallyl (cinnamyl). These are residues I of alcohols of theformula R CH=C(R CHzOH R CH=C(R CHzOCH CHCOOR where R under theseconditions is an alkyl group of not over eight carbon atoms,particularlyan alkyl group of one to four carbon atoms, and R and R havethe significance described above.

It is necessary that during transetherification the: a

reaction temperature be maintained below 150 C.

if the above compounds are to be isolated. For

this purpose the alcohol ROH, which'is displaced, is advantageouslytaken off under reduced pressure. If isolation of a transetherifiedether ester} 4 is not required, the reaction may be carried over thisstage and only the rearranged products isolated.

One may thus start with an ester, (R+O)2CO, of carbonic acid and of asaturated monohydric alcohol, R+OH, where R+ is a non-tertiaryhydrocarbon group, particularly an alkyl group of (not over eight carbonatoms and preferably not over four carbon atoms. By reaction thereofwith acetylene at 20 C. to C. in the presence of a strongly alkalinecatalyst such as an alkalimetal acetylide, an alkali metal alcoholate,or a strongly basic quaternary ammonium alkoxide, there are obtainedsuch acrylates as methyl beta-methoxyacrylate, ethylbeta-ethoxyacrylate, propyl beta-propoxyacrylate, butylbetabutoxyacrylate, hexyl beta-hexoxyacrylate, or

octyl beta-octoxyacrylate, or such propionates as methylbeta,beta-diethoxypropionate, butylbeta,betabeta,beta-dimethoxypropionate, ethyl dibutoxypropionate, oroctyl beta,beta-dioctoxypropionate, or'mixtures of ether acrylate-anddiether propionate. Esters such as allyl betaalloxyacrylate orbeta,beta-dialloxypropionate may likewise be made. Along with thesethere may be obtained ether maleates and diether succinates.

When acetylene is no longer absorbed by the reaction mixture, thecatalyst is destroyed and the reaction mixture separated bydistillation. A fraction containing Jether acrylate and dietherpropionate ma be taken off. This may be heated, desirably under reducedpressure, with an alkali metal acid sulfate and the .propionatedecomposed to acrylate, although this is not essential.

The alkoxy acrylates may then be transetherified by heating them with a2,3-unsaturated alcohol, ROH, such as allyl chlorallyl, 3-chloro-.allyl, 2-bromoallyl, Z-methallyl, 2-ethallyl, 2 butallyl, crotyl, orcinnamyl alcohol or 2-pentenol, Z-hexenol, or Z-heptenol. A mildlyacidic catalyst is used at concentrations of 0.01% to 1% of the weightof the'ether ester. The alcohol ROH is displaced at temperatures between75 C. to C. at normal or reduced pressures. This permits isolation ofthe compound R'OCH=CHC OOR where R is the unsaturated group introduced.

This product is then heated at 150 C. to 250 0., preferably 150 C. to200 C., and is thereby rearranged. The resulting ester of2-hydroxymethylene-4-pentenoic"acid may then be separated, if desired.

Alternatively, the same ester may be obtained by heating an alkylbeta-alkoxyacrylate or beta, beta-dialkoxypropionate'at 150 C.'to 250 C.in the presence of an alkali metal acid sulfate with a beta,gammaunsaturated alcohol, ROH. Transetherification and rearrangement both Joccur. The alcohol displaced is distilled off, the catalyst isdestroyed, and the rearranged product is isolated.

Similarly, an alkyl beta-alkoxyacrylate is heated at 150 C. to 250 -C.in the presence of an alkaline catalyst with an alcohol having ahydrocarbon residue solefinically unsaturateddn... thebeta,gamma-position. Transetherification and transesterification nowboth take place ascompanied by rearrangement of one unsaturated,

group introduced from the beta,gamma-unsatu-f continued at elevatedtemperatures, there may even occur decarbonylation of the last-namedesters to 4-pentenoates.-

There follows a description of the preparation of specific intermediatecompounds in order to illustrate the procedures which have beengenerally set forth above.

Example A In a reaction vessel equipped with a packed distilling columnthere were mixed 500 grams of ethyl beta-ethoxyacrylate, which had beenprepared according to the procedures detailed in appfications SerialNos. 52,607 and 52,608, filed on October 2, 1948, 600 grams of allylalcohol,

and 0.25 grams of sodium hydrogen sulfate. The mixture was heated and atpot temperatures of 100 C. to 120 C. ethyl alcohol was taken offfollowed by a mixture of ethyl alcohol and allyl alcohol. under reducedpressure. At 25-46 C./22 mm. allyl alcohol was taken off and at 51-68C./3 mm. a small fraction of a mixture of allyl alcohol and ethylbeta-alloxyacrylate. There were then distiled 390 grams of ethylbeta-alloxyacrylate at 65'72 C./2-3 mm. This product was redistilled at73 C./3 mm.

Example B A portion of 312 grams of ethyl beta-alloxyacrylate, to whichwas added 5 grams of betanaphthol as a polymerization inhibitor, wasstirred and heated at 150 C. (i 5 C.) for two hours. It was then cooledto C. and mixed with a solution of 80 grams of sodium hydroxide in .500ml. of water, also at 10 C. This mixture was allowed to form layers,which were separated. The aqueous layer was extracted with ethyl ether.The ether extract was combined with the organic layer, the etherevaporated, andunreacted ethyl 5 beta-alloxyacrylate recovered bydistillation. The aqueous layer was rendered acidic by addition ofhydrochloric acid. An organic layer thereupon was formed. It wasseparated from the aqueous layer by extraction with ethyl ether. Theether-organic layer was dried over a calcium sulfate drying agent anddistilled. After the ether had been stripped off, there was obtained afraction of 95 grams distilling at 63-'76 C./2.5

mm. and corresponding in composition to ethyl 2 hydroxymethylene 4pentenoate. This substance was redistilled at -4='7 C./1 mm.

In the above-described preparation but one allyl group was introduced inthe ether acrylate by transetherification. Both transetherification andtransesterification may, however, be effected to introduce two allylicgroups, as will now be shown.

Example C There were mixed in a reaction vessel equipped with a packeddistilling coumn 145 grams of ethyl beta-ethoxyacrylate, 175 grams ofmethallyl alcohol in which five grams of sodium had been dissolved, and200 grams of toluene. The mixture was heatedand an azeotrope of ethanoland toluene taken off at 76 to 85C. while the pot temperature graduallyrose to 125 C. The charge was cooled, poured into water, and acidified.An oil layer formed which was separated, washed with brine, dried, anddistilled. After toluene had been removed, most of the remaining liquidwas distilled between 40 and 140 C. 1

mm. It was washed with 200 ml. of a cold aqueous solution containing 10%of sodium hydroxide. The organic layer was separated, dried The liquidremaining was distilled over anhydrous potassium carbonate, anddistilled. There was obtained 12 grams of methallyl4-methyl-4-pentenoate at 32-40 C./1 mm., 42 grams of methallylbeta-methalloxyacrylate at 40 to C./1 mm., and 2'7 grams of methallylbeta,beta-di(methalloxy)propionate at 85 to C./1 mm.

Example D The methallyl beta-methalloxyacrylate was redistilled at 91-920/3 mm. This was heated to 170-175 C. to cause rearrangement. It wasthen shaken with .200 ml. of a 10% aqueous sodium hydroxide solution.The solution was separated and extracted with ether. This solution andthe sodium hydroxide solution obtained above were acidified by theaddition of hydrochloric acid. The acidic solution was extracted withether and the ether layer separated, dried, and distilled. After removalof ether there was obtained at 64 to 66 C./1 mm. a liquid which wasmethallyl 2-hydroxymethylene-4=-methy1-4-pentenoate.

By these methods there are obtained esters of2-hydroxymethy1ene-4-pentenoic acid and of saturated aliphaticmonohydric alcohols, ROI-I, or of 2,3-unsaturated alcohols, ROH, v

II on These react with carboxylic acid anhydrides, such as aceticanhydride, propionic anhydride,

butyric anhydride, or the like to form the acyloxy derivatives,

RC o 0 CH=OC o o R (or R) 1 A mixture of 157 grams of ethyl2-hydroxymethylene--pentenoate and 220 grams of acetic anhydride washeated in a reaction vessel equipped with a distilling column. Aceticacid was taken off at to 125 C. whereupon a mixture of acetic acid andacetic anhydride was obtained. The reaction mixture was then distilledunder reduced pressure. After the excess acetic anhydride had been takenoif, there was obtained at 75 C./1 mm. grams of ethyl 2-acetoxymethylene-4-pentenoate, having a refractive index of 1.4691.

Example F (a) The procedure of Example E was applied to a mixture ofethyl 2-hydroxymethylene-4-pen- I tens-ate and propionic anhydride.There was obtained at 90-95 C./Q.5 mm. ethyl 2-propionyloxymethylene-4-pentenoate. g

(b) Substitution of butyric anhydride for ace tic brpropionicanhvdrideled to ethyl 2-b tyrxizmethylene-pen eno a .An alternativeapproach to the acylated ester isby heating an alloxyacrylate withacarboxylic acid anhydride. Theoretically, the2-.hydroxymethyleneelepentenoate is formed and acylated. In any case theproduct separated isabeta-acyloxymethylene-4-pentenoate.

Example G .As illustrative of this last method, the following account ofa typical preparation is given. A

mixture of 197 grams of ethyl beta-alloxyacrylate and 255 grams ofacetic anhydride of 90% purity was heated to 150 C. in a flask equippedwith a four-foot packed column. There was taken oil a small amount ofmaterial at overhead temperatures of 60 to 115 C. There was thenobtained at 118-125 C. 76 grams of acetic acid while the pot temperatureadvanced .to 170 C. The pressure within the apparatus was then reducedand excess acetic anhydride taken off. The remaining material wassubjected to fractional distillation at reduced pressure. After a smallforerun a fraction amounting to 170 grams Was obtained at 102 l08 C./2-3mm. It had a refractive index, n of 1.4600, a molecular refraction, MRof 51.41, and a density,

of 1.056. It had a saponification number of 563 and an acid number of284. It contained 59.86% of carbon and 7.33% of hydrogen. These valuesagree well with those calculated for ethylZ-acetoxymethylenel-pentenoate, for which theoretical values aresaponification number568, acid number-Q84, MR 50.76, carbon content60.59%, and hydrogen content7.l2%.

In place of acetic anhydride in the above specific examples, there maybe used other carboxylic acid anhydride to give the corresponding2-acyloxymethylene-4pentenoate such as ethyl2-propionoxymethylene-4-pentencate and ethylZ-butyroxymethylene-4-pentenoate. In place of the ethyl ester, there maybe used other esters, such as methyl, propyl, butyl, hexyl, or octyl, oran alkenyl group, such as allyl, methallyl, crotyl, cinnamyl,chlorallyl, bromallyl, or the like.

Example H ,A mixture of 156 grams (1.0 mole) of ethylbeta-alloxyacrylate and 195 grams (1.5 moles) of propionic anhydride washeated in a Claisen flask at 172-l75 C. while 79 grams (1.07 moles) ofpropionic acid was distilled oil at 133-140 C. "This had a refractiveindex, n of 1.3920. The residue was cooled and the distillation wascontinued in vacuo. After excess propionic anhydride was distilled oilat 3589 C./0.5 mm. in an amount of 92 grams, there was obtained 140grams (66% yield) of ethyl 2-propionoxymethylenel-pentenoate whichdistilled at 89- 97 C./0.5 mm. On redistillation, it boiled at 9294C./0.5 mm. and had an index of refraction, 11 of 1.4597 and a density,

as of 1.029.

Example I A mixture of 156 grams (1.0 mole) of ethyl beta-alloxyacrylateand 237 grams (1.5 moles) of butyric anhydride was heated, in a Claisenflask at 179-202 C. while 94 grams (1 07 moles) ofrbutyriaacid .Whichdistilled at 1'3 ".-.154.c.

was collected. The residue was cooled and .the distil at on wascontinued in vacuo. After removal or 128 grams or Dutyric annydrioe,which (lls'fillleu at air-e5" u./u.5 mm., there was obtained 125 grams(52% yield) of ethyl 2 butyroxymetnylene-e-pentenoate which distilled at95-1uz C./u.e mm. and nad an index of refraction, 11 of 1.4571.

Since the acyioxy group is to be displaced according to this invention,there is ordinarily no advantage in the use or other than the smallestand most economical group, the acetox-y group, in forming theZ-acyloxymethylene substituent. This invention is directed to thereplacement of the acyloxy group, specilically the acetoxy group, andconversion thereof to an alkoxy group.

This is accomplished by heating an ester of the formula R"COOCH=CCOORHURI R: H UB2 with an alcohol, R OH, in the presence of an acidiccatalyst. Temperatures of 50 to or more may be used. Suitable catalystsare phosphoric acid, sulfuric acid, p-toluene sulfonic acid, or otheracid which is efiective in esterification reactions. The acyl group isremoved through formation of an ester with the alcohol, or with thealcohol group from the original 2-acyloxymethylene-4-pentenoate ester,or both. The ester, R"COOR or R"COOR, is removed by volatilization,under reduced pressure if advantageous. The ester-forming group, R, mayalso be replaced with R and the alcohol ROH taken ofi. The productobtained is of the formula ROCH=CCOOR H2 or ROCH=C-COOR HUR isoheptyl,octyl, capryl, decyl, dodecyl, cetyl,

stearyl, cyclohexyl, methylcyclohexyl, or the like, a d groups such asbenzyl, methylbenzyl, hexahydrobenzyl, hydroterpenyl, etc. Unsaturatedhydrocarbon groups, such as allyl, crotyl, cinnamyl, methallyl,ethallyl, propallyl, hexenyl,

undecyl, oleyl, tetrahydrobenzyl, terpenyl,endom:thylenetetrahydrobenzyl, etc. are also of considerable interest,as they give particularly useful and reactive derivatives. When R is a2,3- unsaturated alcohol residue; i. e., an allylic alcohol (R' OI-I),ethers of hydroxymethylene-tpentenoates are obtained which undergo anailylic rearrangement, when heated, to form new unsaturatedaldehydo-carboxylates or malon These lose their aldehyde group: whenheated with an .alkali hydroxide :or an.- Thus, when R has the:

aldehydates.

alkali metal alcoholate.

' ocH-d-o 0211 more structure i-ICR =C(R )CHz,- the following reactionscan occur I I (heat) 1 Example 2 A mixture of 104 grains of ethyl2-acetoxymeth ylene-4-pentenoate, 150 grams of ethanol (anhydrous), andone grain of p-toluene sulfonic acid was heated in a reaction vesselequipped with a four-foot distilling column. There was taken off atl0-80 C. a'mixture of ethanol and ethyl acetate. The remaining liquidwas fractionated through .a packed column under reduced pressure. Therewas obtained '71 grams of ethyl 2-ethoxymethylene-4-pentenoate,distilling at 65-70"C./0.4 mm., having a refractive index, 11 of 1.4644,and containing by analy-- sis 65.46% of carbon and 8.7% of hydrogen.Theoretical values for C10H1803 are 65.20% and 8.76% respectively.

Example 3 A mixture of 198 grams of ethyl 2-acetoxymeth--ylenel-pentenoate, 391 grams of 2-ethyl hexaiio'l, and a half gram ofsulfuric acid was heated in a reaction vessel equipped with distillingcolumn; At 68-'70 C. (overhead) there was taken off ethyl acetate. Whenthe pot tempera ture reached 190 C., distillation under reduced pressurewas resorted to. At 48-80 C./0.2 mm. 169 grams of a mixture of2-ethylhexyl acetate and Z-ethylhexanol was distilled out. There wasthen obtained at 80-12-8 C./0.2 mm. 18 grams of a mixtureof 2-ethylhexylacetate and 2'-ethylhexy 2- (2 -ethylhexoxymethy1ene) -4 -pentenoate.This mixture had a refractive index of 1.4540. At 128-'190 C./0.2 mm.there was obmm. It then had a reiractive index, n of iii! ' bromine as Ror R 16 1.4658 and had a saponification equivalent of 360. Thetheoretical number is 352.

' Example 4 A mixture of 00 grams of ethyl Z-acetoxymetliylene-4-pentenoate, 200 grams 'of cyclohexanol, and two grams ofphosphoric acid was heated in a reaction vessel carrying a shortdistilling column. At 58-79 C. there was obtained in an amount of 45grams ethyl acetate. When the pot temperature reached 164 C.,distillation un der reduced pressure was used. At 45-57 C./1 mm. gramsof cyclohexanol was taken off, At 118 to 152 C./1-2 mm. 71 grams ofcyclohexyl 2-cyclohexoxymethylene-4-pentenoate was obtained with slightdecomposition occurring in the pot as shown by evolution of gas. Theproduct was redistilled at -144 C./0.2 mm. It then had a refractiveindex of 1.5025 and a saponification equivalent of 300 (theory is 292).

In place of the ethyl ester of 2-acyloxymethylene-4-pentenoic acid usedabove, there may be used in place of the ethyl group the methyl, propyl,butyl, amyl, hexyl, heptyl, or octyl group with similar results. It willbe noted that the alcohol residue of the starting ester may be replacedduring the reaction. When the esterforming group is thus replaced withthe residue B, it is, of course, desirable that the original ester haveonly a small alcohol residue as the ester-forming group, such as methylor ethyl. Hence, methyl or ethyl 2-acetoXymethylene-4- pentenoates arepreferred as starting materials. The pentenoate chain may have methyl,ethyl. propyl, butyl, or phenyl groups or chlorine or These substituentsare not disturbed in the above-described reactions.

The reaction of a 2,3-unsaturated alcohol of the formula v R CH=C (RCH2OH with an ester of a 2-acyloxymethylene-4-pentenoate is a specialcase, for, as has been already indicated, not only is the acyl groupdisplaced, but a rearrangement of the alloxymethylenc group can occurand occurs increasingly as the temperature is raised. Thus, while theprimary reaction below C. is replacement of the acyl group, above 150 C.replacement is accompanied by rearrangement. When the rearranged productis that desired, the acyloxymethylene-4- pentenoate may be heated withan allylic alcohol at 150 C. to 250 C. in the presenceof catalyst andthe rearranged product separated.

Example 5 A mixture of 100 grams of ethyl2-acetoxymethylene-4-pentenoate, 87 grams of allyl alcohol, one gram ofp-toluene sulfonic acid, and two grams of beta-naphthol was heated in areaction vessel equipped with a distilling column. A distillate wastaken oil" at 30-82 C. which contained some water. At 829'7 C. a mixtureof allyl acetate and allyl alcohol was obtained. Excess allyl alcoholwas stripped oif under reduced pressure. The remaining liquid wasfractionally distilled. Between 78 and 99 C./ 1 mm. there was obtained adistillate which was chiefly allyl Z-alloxymethylene-4-pentenoate.Between 100 C. and 135 C./1 mm. the distillate was a mixture of allyldiallylmalonaldehydate and allyl 2-alloxymethylenel-pentenoate. This washeated to 220 C. and subjected to fractional distillation. There wasobtained at 67-68 C./1 mm. or 73-75 C./2 mm. a liquid, for which n was1.4532,

11 was 0.997, and the. saponification equivalent was 104. Thiscorresponded in composition to allyl diallylmalonaldehydate,

which requires two moles of alkali for complete reaction, since theester is saponified and the aldehyde group is cleaved to yield formate.In place of the allyl alcohol shown above, there may be used chlorallyl,bromoallyl, crotyl, 3-ethallyl, 3-buta1lyl, or cinnamyl alcohols. Inevery case the acyl group is displaced and a new ether formed, whichundergoes rearrangement. When the allylic group is hydrocarbon, themalonaldehydate yields, when heated with alkali, such as potassiumhydroxide or a sodium alcoholate, allyl diallylacetate and potassium orsodium formate.

Examplefi A mixture of 106 grams (0.5 mole) of ethyl 2-propionoxymethylene-l-pentenoate, 108 grams (1.5 moles) of crotylalcohol, and 1 gram of ptoluene'sulfonic acid was heated under a twofootcolumn. There was obtained on distillation a mixture of 9 grams of waterand 50 grams of ethyl propionate, which distilled at 75-100 C. While thepot temperature rose from 100 C. to 125 C. The remaining crotyl alcoholwas stripped under reduced pressure. The residue was heated at 220 C.for minutes, cooled, and then distilled from a Claisen flask in vacuo.There was obtained 60 grams of crotyl allyl-(1- methallyl)malonaldehydate which boiled at 80-90 C./ 2 mm. The residue whichconsisted of a heavy tar weighed 51 grams. On redistillation the productboiled at 8285 C./2 mm., had an index of refraction, 11 of 1.4492, andgave upon analysis a saponification equivalent of 115. Crotyl allyl (1methallyl) malonaldehydate (Cl4H2003) calculated as a dibasic acid esterhas a saponification equivalent of 118. The 60 grams of productrepresents a yield-of 51%.

Example 7 A solution of ml. of anhydrous ethanol containing one gram ofdissolved sodium and 23.6 grams (0.10 mole) of crotylallyl-(l-methallyl) malonaldehydate was heated under a one-foot column.There was obtained on fractional distillation 7.5 grams of ethyl formatewhich boiled at 52-58C. and had a refractive index, n of 1.3600. Theexcess ethanol was stripped under low pressure and the residue wasdistilled from a Claisen flask in vacuo. There was obtained 15 grams(72% yield) of crotyl 2-allyl-3-methyl-4- pentenoate which distilled at64'-68' C./2 mm., had a refractive index, 12 of 1.4408, and had,

by analysis, a saponification equivalent of 200.

For crotyl 2 allyl 3 methyl 4 pentenoate (C13H20O2) the theoreticalsaponification equivalent is 208.

We claim:

1. The process of preparing unsaturated malonaldehydates which comprisesheating at a temperature from 150 C. to 250 C. a compound of the formulaRICH=C(R4)CHZO CH=C-COOR H(|3R ii on2 wherein R is a non-tertiaryhydrocarbon group of not over eighteen carbon atoms and obtaining acompound of the structure mcrrckno=om OCH- -coon wherein R R R and R aremembers of the class consisting of hydrogen, alkyl groups of not overfour carbon atoms, and the phenyl group, at least one of the pair of Rand 1'1. and of the pair of R. and R being hydrogen.

2. The process of preparing unsaturated malonaldehydates which comprisesheating at a temperature from C. to 250 C. a compound of the formulawherein R is a non-tertiary hydrocarbon group of not over nine. carbonatoms and obtaining a compound of the structure CHzCH=CH 3. The processof preparing malonaldehydates which comprises heating together in thepresence of an acidic catalyst at a temperature of 150 C. to 250 C. acompound of the formula a -HC(R)=CH'2,

and an alcoholv of the'formula R CH=C (R CH2OH and separating a productof the-formula R1 HC(R )=C'H' wherein R is an alkyl group of not-overthreecarbon atoms, R is a. non-tertiary hydrocarbon group of not overnine carbon atoms, and R R R and R are. members of the, class.consisting of hydrogen, alkyl groups of not over four carbon. atoms, andthe phenyl, group, at least one of the-pair of R and R and-of the pairof R and R4 being hydrogen.

4. The process which comprises heating together in the presence ofanalcoholysis catalyst at atemperature of 150 C. to 250 C. a com,- poundof the formula.

HZCH=CH2 and allyl alcohol and separating a product of theformula OCH?OHQCH=CH1 OHC- j-cooa '112cH=o.H1. wherein-.R is a nonetertiaryhydrocarbongroup of -not over ninev carbonatoms.

5. The; process which comprises heating to,- gether, in the presence; ofan-alcoholysis' catalyst at a temperature of 150 C. to 250 C. a compoundof the formula.

H2CH=CH2 and-allyl alcohol, CH2=CHCH2OH, andseparating a product. oftheformula CH2C'H=C'HL5 oHo- -coocn,cn=o n H' CH'-=CH:

JOHN O. VAN HOOK. WILLARD J; CROXAIJL.

No references cited.

1. THE PROCESS OF PREPARING UNSATURATED MALONALDEHYDATES WHICH COMPRISESHEATING AT A TEMPERATURE FROM 150* C. TO 250* C.A COMPOUND OF THEFORMULA